ModelSamplingFlux_motorway_edition

ModelSamplingFlux_motorway_edition is the Motorway-pack version of ComfyUI's ModelSamplingFlux: it applies Flux's timestep-shift settings to a model, but reads the model from the MOTORWAY 🚌💨 bus by key instead of over a wire.

The native node exists because Flux - and other flow-matching models - are picky about where their sampling steps land. max_shift (default 1.15) and base_shift (default 0.5) define the shift curve, and width/height (both default 1024) matter because Flux's shift is resolution-dependent: a 1:1 image at 2048 wants a different curve than the same image at 1024. Get it wrong and you get the classic flow-model symptoms - over-smoothed mush, or a final image that's mostly noise with detail only appearing in the last step. Get it right and Flux just behaves. It's the node most "why does Flux look bad at high resolution" answers point to.

What the motorway edition changes

Generated by clone_nodes_in_the_dangerzone/nodes.py, so the interface is: MOTORWAY 🚌💨 in (required), the native widgets (max_shift, base_shift, width, height), and two key strings:

• INPUT_model_key (default model) - bus key holding the model to shift.
• OUTPUT_MODEL_key (default MODEL) - bus key the shifted model is written to.

It pulls the model out, applies the shift, stores it back under MODEL, and outputs only the cloned bus. You pull MODEL off later (a Motorway 0x1 with key MODEL) and feed your sampler. One-for-one swap for the native node inside a Motorway graph.

Installing

cd ComfyUI/custom_nodes
git clone https://github.com/agilly1989/ComfyUI_agilly1989_motorway

or ComfyUI Manager → "ComfyUI_agilly1989_motorway", then restart. No pip deps, no model downloads.

The fragility you should know about

This is the sketchiest part of the pack, and the author's naming agrees: the clones live in clone_nodes_in_the_dangerzone. They're generated at import time over every node ComfyUI has registered, which has crashed people's startups in the wild - a 2025 report shows an unrelated RandomModelClipVae class missing a CATEGORY attribute taking down the whole Motorway import. The README also flags that custom-JS and output nodes won't clone cleanly.

And the 1.1.7 hotfix disabled the clone loader entirely, so on current versions this node may not be registered - if it's missing from your menu, that's expected, not your fault. If you're not already living on the Motorway bus, use the native ModelSamplingFlux; it's the same math with none of the risk.